Biochemical characterization of the 49 kDa penicillin-binding protein of Mycobacterium smegmatis

摘要

pThe 49 kDa penicillin-binding protein (PBP) of iMycobacterium smegmatis/i catalyses the hydrolysis of the peptide or iS/i-ester bond of carbonyl donors Rsub1/sub-CONH-CHRsub2/sub-COX-CHRsub3/sub-COOsup-/sup (where X is NH or S). In the presence of a suitable amino acceptor, the reaction partitions between the transpeptidation and hydrolysis pathways, with the amino acceptor behaving as a simple alternative nucleophile at the level of the acyl-enzyme. By virtue of its N-terminal sequence similarity, the 49 kDa PBP represents one of the class of monofunctional low-molecular-mass PBPs. An immunologically related protein of iM/isubr/sub 52000 is present in iM. tuberculosis/i. The 49 kDa PBP is sensitive towards amoxycillin, imipenem, flomoxef and cefoxitin./p